The invention relates to piping or tubular structures, for use in an oil or gas environment, wherein the piping is provided with an RFID tag for identification purposes.
During drilling operations, for example as it is common in connection with the recovery of petroleum, a relatively great number of pipes are used, the pipes being screwed together into a pipe string. The pipe string may also include other equipment, for example controls and valve sections. A well of this kind is normally lined with casing in order to secure the borehole. In order to keep track of the number of pieces of equipment and their physical condition, it has turned out to be useful to monitor the service time and stresses of the individual pipes and associated equipment, and also to keep track of the number and where the individual pipe is located in the pipe string.
It is known for an electronic ID tag to be placed on the pipe or equipment, which is read manually by means of matched equipment when the pipe is run into the well and when it is pulled from the well. U.S. Pat. No. 5,142,128 thus discloses an apparatus for identifying equipment related to the recovery of oil, which is also arranged to keep track of the service time of the equipment. The document describes a hand-held reading device for electronic ID tags.
Electronic ID tags of the kind concerned here, are mounted on the outside of the pipes near the connecting means of the pipes. Thereby, the ID tags can be read when passing an antenna. This positioning entails that the ID tags are subjected to wear during the moving of the pipe in the borehole and to damage from, for example, power tongs during make-up and break-out operations. It has also turned out that the attachment of the ID tags in the pipes is adversely affected by relatively large pressure variations in the well.
Equipment according to the prior art exhibits drawbacks related to applicability and/or reliability, as, among other things, the range of signals from the ID tags is relatively small, the ID tags are subjected to wear and may be damaged during the assembling of the pipes.
WO2006/041306A1, which is from a patent family owned by the applicant, discloses an RFID system that is provided on a pipe segment for identification purposes. WO2006/041306A1 is incorporated by reference in its entirety. In this specification, conventional RFID technology as such is considered to be well known and will therefore not be further explained. Various RFID tags having various dimensions are available on the market. The current disclosure does not aim to improve upon those tags as such, nor upon the system for reading such RFID tags when provided on a piping or tubing.